scholarly journals Asexual Evolution and Forest Conditions Drive Genetic Parallelism in Phytophthora ramorum

2020 ◽  
Vol 8 (6) ◽  
pp. 940 ◽  
Author(s):  
Jennifer David Yuzon ◽  
Renaud Travadon ◽  
Mathu Malar C ◽  
Sucheta Tripathy ◽  
Nathan Rank ◽  
...  
Keyword(s):  
Parallel Evolution ◽  
Host Density ◽  
Phytophthora Ramorum ◽  
Environmental Data ◽  
Ancestral State ◽  
Isolated Populations ◽  
Asexual Population ◽  
Unusual Phenomenon ◽  
Repeated Evolution ◽  
Forest Conditions

It is commonly assumed that asexual lineages are short-lived evolutionarily, yet many asexual organisms can generate genetic and phenotypic variation, providing an avenue for further evolution. Previous work on the asexual plant pathogen Phytophthora ramorum NA1 revealed considerable genetic variation in the form of Structural Variants (SVs). To better understand how SVs arise and their significance to the California NA1 population, we studied the evolutionary histories of SVs and the forest conditions associated with their emergence. Ancestral state reconstruction suggests that SVs arose by somatic mutations among multiple independent lineages, rather than by recombination. We asked if this unusual phenomenon of parallel evolution between isolated populations is transmitted to extant lineages and found that SVs persist longer in a population if their genetic background had a lower mutation load. Genetic parallelism was also found in geographically distant demes where forest conditions such as host density, solar radiation, and temperature, were similar. Parallel SVs overlap with genes involved in pathogenicity such as RXLRs and have the potential to change the course of an epidemic. By combining genomics and environmental data, we identified an unexpected pattern of repeated evolution in an asexual population and identified environmental factors potentially driving this phenomenon.

scholarly journals Parallel evolution and ecological selection: replicated character displacement in spadefoot toads

2009 ◽  
Vol 276 (1676) ◽  
pp. 4189-4196 ◽  
Author(s):  
Amber M. Rice ◽  
Aaron R. Leichty ◽  
David W. Pfennig
Keyword(s):  
Resource Competition ◽  
Parallel Evolution ◽  
Character Displacement ◽  
Population History ◽  
Ancestral Population ◽  
Sympatric Populations ◽  
Trait Evolution ◽  
Ecological Selection ◽  
Spadefoot Toads ◽  
Repeated Evolution

Ecological character displacement—trait evolution stemming from selection to lessen resource competition between species—is most often inferred from a pattern in which species differ in resource-use traits in sympatry but not in allopatry, and in which sympatric populations within each species differ from conspecific allopatric populations. Yet, without information on population history, the presence of a divergent phenotype in multiple sympatric populations does not necessarily imply that there has been repeated evolution of character displacement. Instead, such a pattern may arise if there has been character displacement in a single ancestral population, followed by gene flow carrying the divergent phenotype into multiple, derived, sympatric populations. Here, we evaluate the likelihood of such historical events versus ongoing ecological selection in generating divergence in trophic morphology between multiple populations of spadefoot toad ( Spea multiplicata ) tadpoles that are in sympatry with a heterospecific and those that are in allopatry. We present both phylogenetic and population genetic evidence indicating that the same divergent trait, which minimizes resource competition with the heterospecific, has arisen independently in multiple sympatric populations. These data, therefore, provide strong indirect support for competition's role in divergent trait evolution.

scholarly journals Insights into the ancestral flowers of Ranunculales

2020 ◽  
Vol 194 (1) ◽  
pp. 23-46 ◽  
Author(s):  
Laetitia Carrive ◽  
Boris Domenech ◽  
Hervé Sauquet ◽  
Florian Jabbour ◽  
Catherine Damerval ◽  
...  
Keyword(s):  
Floral Organ ◽  
Ancestral State ◽  
Sources Of Uncertainty ◽  
Single Origin ◽  
Reconstruction Methods ◽  
Floral Diversity ◽  
Organ Identity ◽  
Repeated Evolution ◽  
Phylogenetic Framework ◽  
Ordinal Level

Abstract The question of the origin of petals has long been debated in the botanical literature. Ranunculales are characterized by a spectacular floral diversity, particularly at the perianth level. Recent progress in understanding the genetic bases of floral organ identity suggests a single origin for petals in Ranunculaceae, contrasting with the traditional morphological hypothesis of repeated evolution. However, perianth evolution at the ordinal level remains incompletely understood. Recent advances in the elucidation of phylogenetic relationships in the order now provide a new opportunity to study character evolution with model-based methods. We used ancestral state reconstruction methods that take into account various sources of uncertainty to reconstruct the evolution of floral traits at the scale of Ranunculales using a consensus phylogenetic framework of 144 terminal species representing all families in the order. Ancestrally, Ranunculales probably had three trimerous whorls of perianth organs differentiated into two categories of petaloid organs differing in their shape. Each whorl was further lost or duplicated. Moreover, our results support the hypothesis of a single origin of highly specialized (elaborate) nectariferous petals in Ranunculaceae.

scholarly journals Parallel Evolution of Complex Centipede Venoms Revealed by Comparative Proteotranscriptomic Analyses

2019 ◽  
Vol 36 (12) ◽  
pp. 2748-2763 ◽  
Author(s):  
Ronald A Jenner ◽  
Bjoern M von Reumont ◽  
Lahcen I Campbell ◽  
Eivind A B Undheim
Keyword(s):  
Parallel Evolution ◽  
Structural Diversity ◽  
Gene Families ◽  
Toxin Gene ◽  
Ancestral State ◽  
Gene Trees ◽  
Single Family ◽  
Strong Constraint ◽  
Compositional Evolution ◽  
Extant Species

Abstract Centipedes are among the most ancient groups of venomous predatory arthropods. Extant species belong to five orders, but our understanding of the composition and evolution of centipede venoms is based almost exclusively on one order, Scolopendromorpha. To gain a broader and less biased understanding we performed a comparative proteotranscriptomic analysis of centipede venoms from all five orders, including the first venom profiles for the orders Lithobiomorpha, Craterostigmomorpha, and Geophilomorpha. Our results reveal an astonishing structural diversity of venom components, with 93 phylogenetically distinct protein and peptide families. Proteomically-annotated gene trees of these putative toxin families show that centipede venom composition is highly dynamic across macroevolutionary timescales, with numerous gene duplications as well as functional recruitments and losses of toxin gene families. Strikingly, not a single family is found in the venoms of representatives of all five orders, with 67 families being unique for single orders. Ancestral state reconstructions reveal that centipede venom originated as a simple cocktail comprising just four toxin families, with very little compositional evolution happening during the approximately 50 My before the living orders had diverged. Venom complexity then increased in parallel within the orders, with scolopendromorphs evolving particularly complex venoms. Our results show that even venoms composed of toxins evolving under the strong constraint of negative selection can have striking evolutionary plasticity on the compositional level. We show that the functional recruitments and losses of toxin families that shape centipede venom arsenals are not concentrated early in their evolutionary history, but happen frequently throughout.

Endoparasite species richness of New Caledonian butterfly fishes: host density and diet matter

Parasitology ◽  
2000 ◽  
Vol 121 (1) ◽  
pp. 65-73 ◽  
Author(s):  
S. MORAND ◽  
T. H. CRIBB ◽  
M. KULBICKI ◽  
M. C. RIGBY ◽  
C. CHAUVET ◽  
...  
Keyword(s):  
Species Richness ◽  
Coral Reef ◽  
Parasite Species ◽  
New Caledonia ◽  
Ecological Factors ◽  
Host Density ◽  
Reef Fishes ◽  
Coral Reef Fishes ◽  
Ancestral State ◽  
Parasite Species Richness

Ecological factors may influence the number of parasites encountered and, thus, parasite species richness. These factors include diet, gregarity, conspecific and total host density, habitat, body size, vagility, and migration. One means of examining the influence of these factors on parasite species richness is through a comparative analysis of the parasites of different, but related, host species. In contrast to most comparative studies of parasite species richness of fish, which have been conducted by using data from the literature, the present study uses data obtained by the investigators. Coral reef fishes vary widely in the above ecological factors and are frequently parasitized by a diverse array of parasites. We, therefore, chose to investigate how the above ecological factors influence parasite species richness in coral reef fishes. We investigated the endoparasite species richness of 21 species of butterfly fishes (Chaetodontidae) of New Caledonia. We mapped the diet characters on the existing butterfly fish phylogeny and found that omnivory appears to be ancestral. We also mapped the estimated endoparasite species richness, coded from low to high parasite species richness, on the existing butterfly fish phylogeny and found that low parasite species richness appears to be associated with the ancestral state of omnivory. Different dietary and social strategies appear to have evolved more than once, with the exception of obligate coralivory, which appears to have evolved only once. Finally, after controlling for phylogenetic relationships, we found that only the percentage of plankton in the diet and conspecific host density were positively correlated with endoparasite species richness.

scholarly journals DNA fragility in the parallel evolution of pelvic reduction in stickleback fish

Science ◽  
2019 ◽  
Vol 363 (6422) ◽  
pp. 81-84 ◽  
Author(s):  
Kathleen T. Xie ◽  
Guliang Wang ◽  
Abbey C. Thompson ◽  
Julia I. Wucherpfennig ◽  
Thomas E. Reimchen ◽  
...  
Keyword(s):  
Gasterosteus Aculeatus ◽  
Parallel Evolution ◽  
Dinucleotide Repeats ◽  
Strand Breaks ◽  
Dna Structures ◽  
Molecular Features ◽  
Repeated Evolution ◽  
Enhancer Sequences

Evolution generates a remarkable breadth of living forms, but many traits evolve repeatedly, by mechanisms that are still poorly understood. A classic example of repeated evolution is the loss of pelvic hindfins in stickleback fish (Gasterosteus aculeatus). Repeated pelvic loss maps to recurrent deletions of a pelvic enhancer of the Pitx1 gene. Here, we identify molecular features contributing to these recurrent deletions. Pitx1 enhancer sequences form alternative DNA structures in vitro and increase double-strand breaks and deletions in vivo. Enhancer mutability depends on DNA replication direction and is caused by TG-dinucleotide repeats. Modeling shows that elevated mutation rates can influence evolution under demographic conditions relevant for sticklebacks and humans. DNA fragility may thus help explain why the same loci are often used repeatedly during parallel adaptive evolution.

scholarly journals Parallel evolution of mound-building and grass-feeding in Australian nasute termites

2017 ◽  
Vol 13 (2) ◽  
pp. 20160665 ◽  
Author(s):  
Daej A. Arab ◽  
Anna Namyatova ◽  
Theodore A. Evans ◽  
Stephen L. Cameron ◽  
David K. Yeates ◽  
...  
Keyword(s):  
Parallel Evolution ◽  
Molecular Dating ◽  
Ancestral State ◽  
Termite Mounds ◽  
Evolutionary Origins ◽  
Functional Aspects ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Nesting Habits ◽  
Ideal Group

Termite mounds built by representatives of the family Termitidae are among the most spectacular constructions in the animal kingdom, reaching 6–8 m in height and housing millions of individuals. Although functional aspects of these structures are well studied, their evolutionary origins remain poorly understood. Australian representatives of the termitid subfamily Nasutitermitinae display a wide variety of nesting habits, making them an ideal group for investigating the evolution of mound building. Because they feed on a variety of substrates, they also provide an opportunity to illuminate the evolution of termite diets. Here, we investigate the evolution of termitid mound building and diet, through a comprehensive molecular phylogenetic analysis of Australian Nasutitermitinae. Molecular dating analysis indicates that the subfamily has colonized Australia on three occasions over the past approximately 20 Myr. Ancestral-state reconstruction showed that mound building arose on multiple occasions and from diverse ancestral nesting habits, including arboreal and wood or soil nesting. Grass feeding appears to have evolved from wood feeding via ancestors that fed on both wood and leaf litter. Our results underscore the adaptability of termites to ancient environmental change, and provide novel examples of parallel evolution of extended phenotypes.

scholarly journals Parallel evolution in Ugandan crater lakes: repeated evolution of limnetic body shapes in haplochromine cichlid fish

2015 ◽  
Vol 15 (1) ◽  
pp. 9 ◽  
Author(s):  
Gonzalo Machado-Schiaffino ◽  
Andreas F Kautt ◽  
Henrik Kusche ◽  
Axel Meyer
Keyword(s):  
Parallel Evolution ◽  
Cichlid Fish ◽  
Crater Lakes ◽  
Haplochromine Cichlid ◽  
Repeated Evolution ◽  
Body Shapes

scholarly journals Coloring inside the lines: genomic architecture and evolution of a widespread color pattern in frogs

2021 ◽  
Author(s):  
Sandra Goutte ◽  
Imtiyaz Hariyani ◽  
Kole Deroy Utzinger ◽  
Yann Bourgeois ◽  
Stephane Boissinot
Keyword(s):  
Evolutionary History ◽  
Genetic Basis ◽  
Molecular Level ◽  
Parallel Evolution ◽  
Color Pattern ◽  
Evolutionary Dynamic ◽  
Ideal System ◽  
Terrestrial Habitats ◽  
History Of ◽  
Repeated Evolution

Traits shared among distantly related lineages are indicators of common evolutionary constraints, at the ecological, physiological or molecular level. The vertebral stripe is a color pattern that is widespread across the anuran phylogeny. Despite its prevalence in the order, surprisingly little is known about the genetic basis and evolutionary dynamic of this color pattern. Here we combine histology, genome- and transcriptome-wide analyses with order-scale phylogenetic comparative analyses to investigate this common phenotype. We show that the vertebral stripe has evolved hundreds of times in the evolutionary history of anurans and is selected for in terrestrial habitats. Using the Ethiopian Ptychadena radiation as a model system, we demonstrate that variation at the ASIP gene is responsible for the different vertebral stripe phenotypes. Alleles associated to these phenotypes are younger than the split between closely related Ptychadena species, thus indicating that the vertebral stripe results from parallel evolution within the group. Our findings demonstrate that this widespread color pattern evolves rapidly and recurrently in terrestrial anurans, and therefore constitute an ideal system to study repeated evolution.

scholarly journals Neural mechanisms underlying the evolvability of behaviour

2011 ◽  
Vol 366 (1574) ◽  
pp. 2086-2099 ◽  
Author(s):  
Paul S. Katz
Keyword(s):  
Parallel Evolution ◽  
Neural Substrates ◽  
Neural Pathways ◽  
Physiological Mechanisms ◽  
Nervous Systems ◽  
Neural Architecture ◽  
Specific Behaviour ◽  
Repeated Evolution ◽  
Species Specific ◽  
Chromatic Sensitivity

The complexity of nervous systems alters the evolvability of behaviour. Complex nervous systems are phylogenetically constrained; nevertheless particular species-specific behaviours have repeatedly evolved, suggesting a predisposition towards those behaviours. Independently evolved behaviours in animals that share a common neural architecture are generally produced by homologous neural structures, homologous neural pathways and even in the case of some invertebrates, homologous identified neurons. Such parallel evolution has been documented in the chromatic sensitivity of visual systems, motor behaviours and complex social behaviours such as pair-bonding. The appearance of homoplasious behaviours produced by homologous neural substrates suggests that there might be features of these nervous systems that favoured the repeated evolution of particular behaviours. Neuromodulation may be one such feature because it allows anatomically defined neural circuitry to be re-purposed. The developmental, genetic and physiological mechanisms that contribute to nervous system complexity may also bias the evolution of behaviour, thereby affecting the evolvability of species-specific behaviour.

scholarly journals Repeated evolution of reproductive isolation in a marine snail: unveiling mechanisms of speciation

2010 ◽  
Vol 365 (1547) ◽  
pp. 1735-1747 ◽  
Author(s):  
Kerstin Johannesson ◽  
Marina Panova ◽  
Petri Kemppainen ◽  
Carl André ◽  
Emilio Rolán-Alvarez ◽  
...  
Keyword(s):  
Gene Flow ◽  
Parallel Evolution ◽  
Hybrid Zones ◽  
Local Site ◽  
Rapid Spread ◽  
Repeated Evolution ◽  
Different Populations ◽  
The Uk ◽  
Candidate Loci ◽  
Selection Group

Distinct ecotypes of the snail Littorina saxatilis , each linked to a specific shore microhabitat, form a mosaic-like pattern with narrow hybrid zones in between, over which gene flow is 10–30% of within-ecotype gene flow. Multi-locus comparisons cluster populations by geographic affinity independent of ecotype, while loci under selection group populations by ecotype. The repeated occurrence of partially reproductively isolated ecotypes and the conflicting patterns in neutral and selected genes can either be explained by separation in allopatry followed by secondary overlap and extensive introgression that homogenizes neutral differences evolved under allopatry, or by repeated evolution in parapatry, or in sympatry, with the same ecotypes appearing in each local site. Data from Spain, the UK and Sweden give stronger support for a non-allopatric model of ecotype formation than for an allopatric model. Several different non-allopatric mechanisms can, however, explain the repeated evolution of the ecotypes: (i) parallel evolution by new mutations in different populations; (ii) evolution from standing genetic variation; and (iii) evolution in concert with rapid spread of new positive mutations among populations inhabiting similar environments. These models make different predictions that can be tested using comprehensive phylogenetic information combined with candidate loci sequencing.

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